Exactly. You could do two sc in say... two or three single sc stitches, one in each sc space between and do the same in the second. And on your next round, keep increasing, do a single sc in each or decrease, depending how big you want your doll to be.

Don't worry. It's not near as complicated as it seems like it should be. First, you should learn this wonderful thing called a 'Magic Loop', you can find it here: http://crochetme.com/Dec_Jan_0405/reads_round.html or you can search for 'magic loop crochet' on YouTube and watch videos. Once you've mastered that, which is very simple, then start your crocheting in the round. When I do it, flat or in the round, I always keep the yarn color that I want to be hidden on top of the rows so when I make my next stitch, the second color is hidden. You can just hold your main color in your hand and only pick up the second one when you need it. It's really simple once you get the hang of it. If you need me to explain that more, I'll be happy to try. Hope that helps.

www.crochetpatterncentral.com then you can go to the section for hats. There's a ton of patterns in there. If you can't find a zig-zag pattern for the hat, you could easily modify a standard circular pattern.